linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Tom Zanussi <zanussi@kernel.org>,
	Namhyung Kim <namhyung@kernel.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Daniel Bristot de Oliveira <bristot@kernel.org>
Subject: [for-linus][PATCH 4/7] trace/osnoise: Print a stop tracing message
Date: Wed, 11 Aug 2021 21:12:54 -0400	[thread overview]
Message-ID: <20210812011355.049731952@goodmis.org> (raw)
In-Reply-To: 20210812011250.954353252@goodmis.org

From: Daniel Bristot de Oliveira <bristot@kernel.org>

When using osnoise/timerlat with stop tracing, sometimes it is
not clear in which CPU the stop condition was hit, mainly
when using some extra events.

Print a message informing in which CPU the trace stopped, like
in the example below:

          <idle>-0       [006] d.h.  2932.676616: #1672599 context    irq timer_latency     34689 ns
          <idle>-0       [006] dNh.  2932.676618: irq_noise: local_timer:236 start 2932.676615639 duration 2391 ns
          <idle>-0       [006] dNh.  2932.676620: irq_noise: virtio0-output.0:47 start 2932.676620180 duration 86 ns
          <idle>-0       [003] d.h.  2932.676621: #1673374 context    irq timer_latency      1200 ns
          <idle>-0       [006] d...  2932.676623: thread_noise: swapper/6:0 start 2932.676615964 duration 4339 ns
          <idle>-0       [003] dNh.  2932.676623: irq_noise: local_timer:236 start 2932.676620597 duration 1881 ns
          <idle>-0       [006] d...  2932.676623: sched_switch: prev_comm=swapper/6 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=timerlat/6 next_pid=852 next_prio=4
      timerlat/6-852     [006] ....  2932.676623: #1672599 context thread timer_latency     41931 ns
          <idle>-0       [003] d...  2932.676623: thread_noise: swapper/3:0 start 2932.676620854 duration 880 ns
          <idle>-0       [003] d...  2932.676624: sched_switch: prev_comm=swapper/3 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=timerlat/3 next_pid=849 next_prio=4
      timerlat/6-852     [006] ....  2932.676624: timerlat_main: stop tracing hit on cpu 6
      timerlat/3-849     [003] ....  2932.676624: #1673374 context thread timer_latency      4310 ns

Link: https://lkml.kernel.org/r/b30a0d7542adba019185f44ee648e60e14923b11.1626598844.git.bristot@kernel.org

Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace_osnoise.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index f9652278bd10..b576e96d9741 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -1075,9 +1075,13 @@ diff_osn_sample_stats(struct osnoise_variables *osn_var, struct osnoise_sample *
 /*
  * osnoise_stop_tracing - Stop tracing and the tracer.
  */
-static void osnoise_stop_tracing(void)
+static __always_inline void osnoise_stop_tracing(void)
 {
 	struct trace_array *tr = osnoise_trace;
+
+	trace_array_printk_buf(tr->array_buffer.buffer, _THIS_IP_,
+			"stop tracing hit on cpu %d\n", smp_processor_id());
+
 	tracer_tracing_off(tr);
 }
 
-- 
2.30.2

  parent reply	other threads:[~2021-08-12  1:14 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-12  1:12 [for-linus][PATCH 0/7] tracing: More fixes for 5.14 Steven Rostedt
2021-08-12  1:12 ` [for-linus][PATCH 1/7] trace/osnoise: Rename main variable to tracer_main Steven Rostedt
2021-08-12  1:12 ` [for-linus][PATCH 2/7] trace/osnoise: Add a header with PREEMPT_RT additional fields Steven Rostedt
2021-08-12  1:12 ` [for-linus][PATCH 3/7] trace/timerlat: " Steven Rostedt
2021-08-12  1:12 ` Steven Rostedt [this message]
2021-08-12  1:12 ` [for-linus][PATCH 5/7] tracing: define needed config DYNAMIC_FTRACE_WITH_ARGS Steven Rostedt
2021-08-12  1:12 ` [for-linus][PATCH 6/7] init: Suppress wrong warning for bootconfig cmdline parameter Steven Rostedt
2021-08-12  1:12 ` [for-linus][PATCH 7/7] tracing / histogram: Fix NULL pointer dereference on strcmp() on NULL event name Steven Rostedt

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210812011355.049731952@goodmis.org \
    --to=rostedt@goodmis.org \
    --cc=akpm@linux-foundation.org \
    --cc=bristot@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mhiramat@kernel.org \
    --cc=mingo@kernel.org \
    --cc=namhyung@kernel.org \
    --cc=zanussi@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).